The present invention relates to hydraulic shock absorbers, especially for use in vehicle suspension systems.
A known hydraulic shock absorber typically includes an inner working cylinder and an outer cylinder extending around the working cylinder so as to define a reservoir therebetween (see FIG. 9). The outer cylinder has an annular collar to which a mounting plate is secured by welding. A damper mechanism is attached to the mounting plate and communicated with the working cylinder through sleeves which are, in turn, inserted through the mounting plate. A problem with the known hydraulic shock absorber is that metal particles ejected during the welding, known as spatter, are introduced into oil within the reservoir, thus resulting in malfunction of the damper mechanism. Removal of such metal particles is cumbersome. Another problem is that an expensive seam weld is required to maintain the seal integrity. Moreover, with a plurality of O-rings placed on the mounting plate, the damper mechanism is secured to the mounting plate to properly position the O-rings. If the O-rings are not properly positioned, oil leakage occurs.
Accordingly, it is an object of the present invention to provide a hydraulic shock absorber which allows a damper mechanism to be mounted to an outer cylinder without the use of welding and enables proper positioning of sealing elements.